Geyser

ABSTRACT

The invention provides a geyser ( 210 ) for heating water in domestic or industrial applications. The geyser ( 210 ) includes a first end section ( 212 ), a second end section ( 214 ), and a central section ( 216 ) between the first and second end sections. The central section ( 216 ) includes a plurality of modular components ( 218  and  220 ) defining an inner wall ( 316 ) which together with the first and second end sections ( 212  and  214 ) forms a primary, sealed chamber (C) for containing fluid within the geyser ( 210 ), in use, and an outer wall ( 318 ), spaced from the inner wall ( 316 ), which together with the inner wall ( 316 ) and the first and second end sections ( 212  and  214 ) forms a secondary, safety chamber (D) for containing fluid expelled from the primary chamber (C) upon failure of the geyser ( 210 ). An outlet ( 331 ) is provided on the geyser ( 210 ) for allowing fluid to discharge from the secondary, safety chamber (D), typically via a vent pipe, to a desired location. The invention also relates to a kit for forming the geyser, and to a method of manufacturing the geyser.

BACKGROUND OF THE INVENTION

THIS invention relates to geysers for heating water in domestic or industrial applications. More specifically, the invention relates to a geyser which is designed to contain heated water in the event of a failure of the geyser. The invention also relates to a kit for forming the geyser, and to a method of manufacturing the geyser.

Conventional geysers for heating water can fail by developing leaks or by bursting unexpectedly. In such an event, the water expelled from the geyser may cause extensive damage. It is thus desirable to have a mechanism for containing water expelled from a failed geyser.

A known method for containing such water is to provide a tray or the like below the geyser. The tray may be connected to a conduit for directing water away from the geyser to a desired location. Although this method generally is effective in containing water discharged directly into the tray, it is not always effective in containing water or steam expelled from the geyser under pressure.

It is an object of the present invention to provide a geyser which includes a mechanism for containing water and steam expelled under pressure upon failure of the geyser.

SUMMARY OF THE INVENTION

According to one aspect of the invention there is provided a geyser comprising:

-   -   a first end section;     -   a second end section;     -   a central section between the first and second end sections, the         central section defining an inner wall which together with the         first and second end sections forms a primary, sealed chamber         for containing fluid within the geyser, in use, and an outer         wall, spaced from the inner wall, which together with the inner         wall and the first and second end sections forms a secondary,         safety chamber for containing fluid expelled from the primary         chamber upon failure of the geyser; and     -   an outlet for allowing fluid to discharge from the secondary,         safety chamber to a desired location.

Ideally, the primary chamber is connected to a vent pipe via a pressure release mechanism, and the secondary chamber is connected to a vent pipe, possibly via a pressure release mechanism.

In one arrangement, the central section includes engaging formations which are engaged with corresponding engaging formations on the first and second end sections. For example, the central section may include female engaging formations at each of two opposed ends thereof, and the first and second end sections may include male engaging formations which are engaged with the female engaging formations on the central section. The connection between the central section of the geyser and each of the first and second end sections may include a seal which may be formed, for example, from an elastomeric material.

In a preferred embodiment of the invention, the central section includes a plurality of modular components which are connected to one another. Each modular component may include an engaging formation which is engaged with a corresponding engaging formation on an adjacent modular component. By way of example, the modular components may include male and/or female engaging components which are engaged with corresponding female and/or male engaging components on adjacent modular components and with corresponding female and/or male engaging components on the first and second end sections. Each connection between adjacent modular components may include a seal, such as an elastomeric seal.

In one form of the invention, the end sections each define a male engaging formation. In this case, the central section may include an adaptor component which includes a female engaging formation at each of two opposed ends, and a plurality of modular components each of which includes a male engaging formation at one end and a female engaging formation at an opposed end, wherein the adaptor is connected at each end to one of the modular components, the first and second end sections are each connected to one of the modular components, and each modular component is connected to at least one other modular component.

Alternatively, the end sections may each define a female engaging formation, in which case the central section may include an adaptor component which includes a male engaging formation at each of two opposed ends, and a plurality of modular components each of which includes a female engaging formation at one end and a male engaging formation at an opposed end, wherein the adaptor is connected at each end to one of the modular components, the first and second end sections are each connected to one of the modular components, and each modular component is connected to at least one other modular component.

In another arrangement, the central section includes two different types of modular components, a first modular component with female engaging formations at each of two opposed ends thereof, and a second modular component with male engaging formations at each of two opposed ends thereof, wherein the first and second end sections are each connected to one of the first modular components, and each second modular component is connected at each end to one of the first modular components.

The engaging formations on the central section or on the modular components of the central section, and the engaging formations on the first and second end sections may be arranged to limit compressive loads applied to the elastomeric seals.

The geyser may include external and/or internal bracing for increased stiffness. For example, the geyser may include reinforcing frames which extend across the inside of the central section to define a row of ribs along the length of the geyser.

In one form of the invention, the geyser includes a screen for limiting the flow of fluid entering the geyser.

The central section may be connected to the first and second end sections with mechanical fasteners. In one embodiment, the mechanical fasteners comprise a plurality of bolts which extend through the first end section and the central section, and which are connected to the second end section by means of a plurality of nuts.

Preferably, the secondary, safety chamber contains an insulation material such as a polyurethane foam.

Ideally, the first and second end sections include end faces which are curved convexly with respect to the primary chamber.

In one embodiment of the invention, the first and second end sections include support formations for supporting the geyser, in use.

The geyser may also include an insulated chamber on at least one of the end sections for insulating at least portions of electrical components for the geyser.

According to a second aspect of the invention there is provided a method of making a geyser comprising the steps of:

-   -   providing a first end section;     -   providing a second end section;     -   providing a central section which defines an inner wall and an         outer wall spaced from the inner wall;     -   connecting the central section to the first and second end         sections so that the inner wall together with the first and         second end sections forms a primary, sealed chamber for         containing fluid within the geyser, in use, and the outer wall         together with the inner wall and the first and second end         sections forms a secondary, safety chamber for containing fluid         expelled from the primary chamber upon failure of the geyser;         and     -   providing an outlet for allowing fluid to discharge from the         secondary, safety chamber to a desired location.

The steps of providing the central section and the first and second end sections may include forming these sections in an injection molding process.

In one arrangement, the step of connecting the central section to the first and second end sections includes locating seals, such as elastomeric seals, between the various sections.

The central section may include a plurality of modular components, and the method may include the step of connecting the modular components together, typically with elastomeric seals, to form the central section.

The central section and/or the first and second end sections may be formed with external and/or internal bracing.

In on embodiment, the end sections and the central section are connected together by means of mechanical fasteners, such as bolts and nuts.

Ideally, the method also includes the step of inserting an insulating material, such as a polyurethane foam, into the secondary chamber.

According to a third aspect of the invention there is provided a kit for forming a geyser comprising:

-   -   a first end section;     -   a second end section;     -   a central section defining an inner wall and an outer wall         spaced from the inner wall, wherein the first section and the         second section are connectable to the central section so that         the inner wall together with the first and second end sections         forms a primary, sealed chamber for containing fluid within the         geyser, in use, and the outer wall together with the inner wall         and the first and second end sections forms a secondary, safety         chamber for containing fluid expelled from the primary chamber         upon failure of the geyser; and     -   an outlet in the first end section, the second end section         and/or the central section for allowing fluid to discharge from         the secondary, safety chamber to a desired location, in use.

Preferably, the central section includes a plurality of modular components which are connectable to one another.

The kit may also include mechanical fasteners for connecting the first end section and the second end section to the central section.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings in which:

FIG. 1 shows a perspective view of a geyser according to one embodiment of the present invention;

FIG. 2 shows a cross-sectional view of the geyser illustrated in FIG. 1;

FIG. 3 shows a rear perspective view of a first end section of the geyser of FIG. 1;

FIG. 4 shows a front perspective view of a second end section of the geyser of FIG. 1;

FIG. 5 shows a perspective view of a first modular component from a central section of the geyser of FIG. 1;

FIG. 6 shows a perspective view of a second modular component from a central section of the geyser of FIG. 1;

FIGS. 7 and 8 show perspective views of a geyser according to a second embodiment of the invention;

FIG. 9 shows a rear perspective view of a first end section of the geyser of FIGS. 7 and 8;

FIG. 10 shows a front perspective view of a second end section of the geyser of FIGS. 7 and 8;

FIG. 11 shows a perspective view of a first modular component from a central section of the geyser of FIGS. 7 and 8;

FIG. 12 shows a perspective view of a second modular component from a central section of the geyser of FIGS. 7 and 8; and

FIG. 13 shows a cross-sectional view of the geyser according to the second embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention may be used in domestic or industrial applications to prevent damage which may be caused by water expelled from a failed geyser.

In FIGS. 1 and 2 of the accompanying drawings there is shown a geyser according to one embodiment of the invention. The geyser is designated generally with the reference numeral 10 and includes a first end section 12, a second end section 14 and a central section 16. The central section 16 includes first modular sections 18 and second modular sections 20 which are connected to one another in a manner described in more detail below.

With reference also to FIG. 3 of the drawings, the first end section 12 is seen to include an end face 22, an inner wall section 24 extending around the end face 22, an outer wall section 26 spaced from the inner wall section 24, and an end wall 28 extending between the inner and outer wall sections. The end face 22 is curved to form a convex surface on the inside of the geyser 10, and includes four inner reinforcing gussets 30, as shown. Eight connection formations 32 are arranged in the space between the inner wall section 24 and the outer wall section 26. Each connection formation 32 includes a socket 34, an inner web 36 connecting the socket to the inner wall section 24, and an outer web 38 connecting the socket to the outer wall section 26. A support in the form of a foot 40 extends from a portion of the outer wall section 26, as shown.

The second end section 14, which is illustrated in FIG. 4, is similar to the first end section 12, and also includes an end face 42, an inner wall section 44 extending around the end face 42, an outer wall section 46 spaced from the inner wall section 44, and an end wall 48 extending between the inner and outer wall sections. Also similar to the first end section 12, the end face 42 is curved to form a convex surface on the inside of the geyser 10, and includes inner reinforcing gussets 50 (see FIG. 2). Eight connection formations 52 are arranged in the space between the inner wall section 44 and the outer wall section 46. The connection formations 52 are similar in all respects to the connection formations 32, and hence also include sockets 54 (visible in FIG. 2), and inner webs 56 and outer webs 58 (also visible in FIG. 2) connecting the sockets to the inner wall section 44 and the outer wall section 46. As in the case of the first end section 12, the second end section 14 includes a supporting foot 60 which extends from a portion of the outer wall section 46, as illustrated.

FIG. 5 illustrates a first modular component 62 for forming the central section 16 of the geyser 10. As can be seen, the first modular component 62 includes an inner wall section 64 and an outer wall section 66. The inner wall section 64 defines a female engaging formation in the form of a channel 68 on each of two opposed sides thereof, and the outer wall section 66 defines a female engaging formation in the form of a channel 70 on each of two opposed sides thereof. The first modular component 62 also includes connection formations 72 which extend between the inner wall section 64 and the outer wall section 66. Each connection formation 72 includes a socket 74, an inner web 76 connecting the socket to the inner wall section 64, and an outer web 78 connecting the socket to the outer wall section 66.

A second modular component 80 is illustrated in FIG. 6. This component is similar to the first modular component 62, and hence also includes an inner wall section 82, an outer wall section 84 and connection formations 86 between the inner and outer wall sections. Each connection formation 86 includes a socket 88, and an inner web 90 and an outer web 92 for connecting the socket to the inner and outer wall sections, respectively. Unlike the first modular component, the inner wall section 82 defines male engaging formations in the form of edges 94 at each of two opposed ends thereof, and the outer wall section 84 defines male engaging formations in the form of edges 96 at each of two opposed ends thereof.

In this embodiment, the first end section, the second end section and the first and second modular components of the central section are all formed in an injection molding process from a polymer material.

In practice, the geyser 10 is assembled by first forming the central section 16, and then connecting the central section to the first end section 12 and the second end section 14. The central section 16 is formed by connecting together a plurality of first modular components 62 and second modular components 80. This may be achieved by placing elastomeric seals (not shown) into the female engaging formations 68 and 70 on the first modular components 62, and then inserting the edges 94 and 96 on the inner wall sections and the outer wall sections of the second modular components into the female engaging formations 68 and 70 to form a length of alternating first and second modular components. The second modular components may include projections (not illustrated) adjacent the edges 94 and 96 which limit the extent to which these edges can penetrate the female engaging formations 68 and 70, thereby to prevent damage to the seals by excessive loading. The number of first and second modular components connected together will depend upon the size of geyser required. Typically, the components 62 and 80 will be sized so that geysers may be formed with capacities of 100 liters, 150 liters or 200 liters, depending upon the number of modular components used to form the central section 16 of the geyser. As can be seen in FIGS. 1 and 2 of the drawings, the central section 16 includes ten first modular sections 18 and nine second modular sections 20, with a first modular section at each end of the central section 16.

Once the central section 16 has been formed, it may be connected to the first end section 12 and the second end section 14 by placing elastomeric seals (not illustrated) into the female engaging formations 68 and 70 at each end of the central section 16, and then inserting the free edges of the inner wall sections and the outer wall sections of the first and second end sections into the female engaging formations 68 and 70. Once again, projections may be provided on the inner and outer wall sections of the first end section 12 and the second end section 14 to limit the extent to which the free edges of these inner and outer wall sections penetrate the female engaging formations 68 and 70, thereby to prevent damage to the seals by excessive loading. In this condition of the geyser 10, the various sockets on the connecting formations are aligned with one another, and the first end section 12, the second end section 14 and the central section 16 are secured together by inserting eight Allen bolts 100 (see FIG. 2) through the various sockets, and locking the Allen bolts to the geyser with nuts 102 (see FIG. 2). In the assembled condition, the central section 16 is sandwiched between the first and second end sections 12 and 14 to form a primary sealed chamber A defined between the inner wall 101 of the central section 16 and the end faces 22 and 42 of the first and second end sections 12 and 14, and a secondary, safety chamber defined between the inner wall 101 of the central section 16, the outer wall 103 of the central section, and the end walls 28 and 48 of the end sections 12 and 14. The primary chamber A is designed to contain fluid under pressure so as to allow water in this chamber to be heated, in use. The secondary, safety chamber is designed to contain fluid expelled from the primary chamber upon failure of the geyser.

With reference again to FIG. 4 of the drawings, the end face 42 includes a first opening 104 for receiving a conventional heating element 106 (see FIG. 2), a second opening 108 defining an inlet for the geyser 10, and a third opening 110 for receiving a conventional thermostat (not illustrated). If desired, the end face 42 could also include an opening 112 for receiving an anode (not illustrated). However, due to the structure and the materials of the geyser 10, it is envisaged that an anode would not be necessary. As shown in FIG. 3, the end face 22 includes an opening 114 defining an outlet for the geyser.

In FIG. 2 of the drawings, an inlet end cap 116 is seen to be connected to the second end section 14, and an outlet end cap 118 is seen to be connected to the first end section 12 with Allen bolts 120. Both end caps 116 and 118 are connected to the end sections with seals or gaskets (not illustrated) so as to form a seal between these components. This allows electrical components such as portions of the heating element and the thermostat to be electrically insulated within the geyser 10. An insulation material, which may comprise, for example, a polyurethane foam 122 (see FIG. 2) may then be introduced into the secondary chamber via a sealable aperture (not illustrated). The polyurethane foam may also be introduced into the gap between the inlet end cap 116 and the second end section 14, and between the outlet end cap 118 and the first end section 12.

In use, the geyser may be installed internally or externally by positioning it on the support feet 40 and 60, and connecting the inlet opening 108 on the second end section 14 to a water supply line extending through an opening 124 in the inlet cap 116 to allow water into the geyser. Conventional valve mechanisms (not illustrated) may be installed to control the flow of fluid through the inlet opening 108, and to allow for the release of pressurized fluid from the primary chamber A when the fluid pressure within this chamber reaches a predetermined magnitude. The geyser 10 may then be connected to a supply of electricity so as to heat water within the primary chamber A, and the heated water may be allowed to drain from the geyser through the outlet opening 114 in a conventional manner. In the event that the geyser fails, for example if the inner wall 101 bursts or develops a leak, in use, water expelled from the primary chamber A is discharged into the secondary, safety chamber where it is contained to prevent damage. A safety outlet on the geyser 10 allows water to discharge from the secondary, safety chamber to a desired location, away from where it can cause damage, via a vent pipe (not illustrated) or the like. If desired, a pressure release mechanism (not illustrated) may be provided to regulate the discharge of water through the safety outlet on the geyser 10.

FIGS. 7 to 13 of the drawings illustrate a geyser 210 according to another embodiment of the invention. In this embodiment, the geyser 210 is similar in many respects to the geyser 10 illustrated in FIGS. 1 to 6, and also includes a first end section 212, a second end section 214 and a central section 216 (see FIGS. 7 and 8). As in the case of the first embodiment, the central section 216 includes first modular sections 218 and second modular sections 220 which are connected to one another to form a geyser with a desired capacity.

With reference also to FIG. 9 of the drawings, the first end section 212 is seen to include an end face 222, an inner wall section 224 extending around the end face 222, an outer wall section 226 spaced from the inner wall section 224, and an end wall 228 (see FIGS. 7 and 8) extending between the inner and outer wall sections. The end face 222 is curved to form a convex surface on the inside of the geyser 210, and includes four outer reinforcing gussets 230, as shown in FIG. 8. Connection formations 232 are arranged in the space between the inner wall section 224 and the outer wall section 226. As can be seen, each of the connection formations 232 includes a socket 234, an inner web 236 connecting the socket to the inner wall section 224, and an outer web 238 connecting the socket to the outer wall section 226. Between the connection formations 232, the end section 212 includes eight reinforcing ribs 239 for increasing the stiffness of this end section, and on an operatively lower portion of this end section, the outer wall section 226 caries a support in the form of a foot 240.

The second end section 214, which is illustrated in FIG. 10, is similar to the first end section 212, and also includes an end face 242, an inner wall section 244 extending around the end face 242, an outer wall section 246 spaced from the inner wall section 244, and an end wall 248 extending between the inner and outer wall sections. Also similar to the first end section 212, the end face 242 is curved to form a convex surface on the inside of the geyser 210, and includes outer reinforcing gussets 250, as shown. Connection formations 252 are arranged in the space between the inner wall section 244 and the outer wall section 246, and similarly to the connection formations 232 in the first end section 212 include sockets (not visible), and inner webs and outer webs (also not visible) connecting the sockets to the inner wall section 244 and the outer wall section 246. Eight reinforcing ribs (not visible) similar to the reinforcing ribs 239 on the first end section 212 are arranged between the connecting formations 252 in the second end section 214, and the second end section carries a foot 254 on the outer wall section 246.

FIG. 11 illustrates a first modular component 256 for forming the central section 216 of the geyser 210. As can be seen, the first modular component 256 includes an inner wall section 258 and an outer wall section 260. The inner wall section 258 defines a female engaging formation in the form of a channel 262 on each of two opposed sides thereof, and the outer wall section 260 defines a female engaging formation in the form of a channel 264 on each of two opposed sides thereof. The first modular component 256 also includes connection formations 266 which extend between the inner wall section 258 and the outer wall section 260. Each connection formation 266 includes a socket 268, an inner web 270 connecting the socket to the inner wall section 258, and an outer web 272 connecting the socket to the outer wall section 260. Between the connection formations 266, the first modular component 256 includes reinforcing ribs 274 for increasing the stiffness of this component. Furthermore, the first modular component 256 includes an inner reinforcing frame 276. In this embodiment of the invention, the inner reinforcing frame 276 includes an outer rim 278 connected to the inner wall section 258, a central portion 280, and four ties 282 extending between the central portion 280 and the outer rim 278.

A second modular component 290 is illustrated in FIG. 12. This component is similar to the first modular component 256, and hence also includes an inner wall section 292, an outer wall section 294 and connection formations 296 between the inner and outer wall sections. Each connection formation 296 includes a socket 298, and an inner web 300 and an outer web 302 for connecting the socket to the inner and outer wall sections, respectively. Between the connection formations 296, the second modular component 290 includes eight reinforcing ribs 304, and the second modular component 290 includes an inner reinforcing frame 306 which includes a central portion 308, and four ties 310 extending between the central portion 308 and the inner wall section 292. Unlike the first modular component 256, the inner wall section 292 defines male engaging formations in the form of edges 312 at each of two opposed ends thereof, and the outer wall section 294 defines male engaging formations in the form of edges 314 at each of two opposed ends thereof.

In FIG. 13, the inner reinforcing frames 276 and 306 are seen to provide a row of internal ribs which, together with the reinforcing ribs 274 and 304 on the first and second modular components 256 and 290, serve to increase the stiffness of the geyser 210.

As in the case of the geyser 10, the various modular components and end sections of the geyser 210 may be formed from a polymer material and the geyser 210 may be assembled in a manner similar to that described above with reference to the geyser 10 by first forming the central section 216, and then connecting the central section to the first end section 212 and the second end section 214.

With particular reference to FIG. 13, the first modular components 256 are seen to include shoulders 320 within the female engaging formations which limit the extent to which elastomeric seals 322 can be compressed by the male engaging formations on the second modular components 290. This ensures that the seals 322 are not damaged during assembly.

In the assembled condition, the central section 216 is sandwiched between the first and second end sections 212 and 214 to form a primary sealed chamber C between the inner wall 316 of the central section 216 and the end faces 222 and 242 of the first and second end sections 212 and 214, and a secondary, safety chamber between the inner wall 316 of the central section 216, the outer wall 318 of the central section 216, and the end walls 228 and 248 of the end sections 212 and 214. As in the case of the geyser 10, the primary chamber C is designed to contain fluid under pressure so as to allow water within this chamber to be heated, in use, and the secondary, safety chamber is designed to contain fluid expelled from the primary chamber upon failure of the geyser.

With reference to FIGS. 9 and 13 of the drawings, the end face 222 is seen to include a first opening 324 for receiving a conventional heating element 326, a second opening 328 defining an inlet for the geyser 210, and a third opening 330 for receiving a conventional thermostat (not illustrated). The first end section 212 is also seen in FIGS. 1 and 13 to include a safety outlet 331 in the end wall 228 which, upon failure of the primary chamber C, allows water collecting in the secondary, safety chamber to discharge via a vent pipe to a desired location away from where it can cause damage. In FIG. 10 of the drawings, the end face 242 is shown with an outlet for the geyser in the form of an opening 332.

Similarly to the geyser 10, the ends of the geyser 210 may be fitted with end caps 334 to allow electrical components such as portions of the heating element and the thermostat to be electrically insulated within the geyser 210. Furthermore, an insulation material may be introduced into the secondary chamber via a sealable aperture (not illustrated) in a manner similar to that described above with reference to the geyser 10, and the geyser 210 may be installed in a similar fashion to that described above with reference to the first embodiment of the invention.

The geyser 210 may include pressure release mechanisms (not illustrated) for regulating the discharge of water from the primary chamber C and/or from the secondary, safety chamber.

Although not shown, the geyser 210 could include a screen inside the primary chamber C for limiting the flow of cool water entering the geyser. For example, the screen could be supported on a portion of the inner reinforcing frames 276 and 306 to cause the cool water initially to remain in the vicinity of the heating element 326 and, subsequent to initial heating, to allow this water to circulate upwardly into contact with heated water within the geyser.

It will be appreciated that various changes could be made to the geysers described above with reference to FIGS. 1 to 6 and FIGS. 7 to 13 of the drawings. For example, the central section of the geyser, instead of including two different types of modular components, may be formed from a plurality of similar modular components, each of which includes female engaging formations on one end thereof and corresponding male engaging formations on the other end thereof so as to be engagable with one another end-to-end to form a row of adjacent modular components. In such an arrangement, one end section of the geyser could include a female engaging formation for engaging a male engaging formation at one end of the central section, and the other end section of the geyser could include a male engaging formation for engaging a female engaging formation at the other end of the central section. Alternatively, if both end sections of the geyser include male engaging formations or female engaging formations, the geyser could include an adaptor for allowing both end sections of the geyser to engage the central section.

It should be appreciated from the foregoing that the secondary, safety chamber of the geyser of the invention is advantageous in that it serves to prevent damage by containing water expelled from the primary chamber of the geyser in the event of geyser failure. It should also be understood that the discharge of water from the secondary, safety chamber to the desired location serves to indicate that the geyser has failed. In this way, the geyser may be repaired or replaced before it effects serious damage. Furthermore, the modular structure of the geyser allows for the cost effective and relatively easy manufacture of different capacity geysers. Also, by forming the central section of the geyser with modular components, geyser failures in the form of cracks tend to be limited to one or two modular components rather than to spread across the length of the geyser. Yet a further advantage of the geyser according to the invention is that it may be formed predominantly from a polymer material. Apart from allowing for the manufacture of geysers which are relatively strong and durable, this renders the geysers resistant to corrosion and avoids the need for anodes. 

1. A geyser comprising: a first end section; a second end section; a central section between the first and second end sections, the central section defining an inner wall which together with the first and second end sections forms a primary, sealed chamber for containing fluid within the geyser, in use, and an outer wall, spaced from the inner wall, which together with the inner wall and the first and second end sections forms a secondary, safety chamber for containing fluid expelled from the primary chamber upon failure of the geyser; and an outlet for allowing fluid to discharge from the secondary, safety chamber to a desired location.
 2. A geyser according to claim 1, including a vent pipe for carrying fluid discharged from the secondary, safety chamber to the desired location.
 3. A geyser according to claim 2, including a pressure release mechanism for regulating the discharge of fluid from the secondary, safety chamber.
 4. A geyser according to claim 1, wherein the primary chamber is connected to a vent pipe via a pressure release mechanism.
 5. A geyser according to claim 1, wherein the central section includes male and/or female engaging formations which are engaged with corresponding female and/or male engaging formations on the first and second end sections.
 6. A geyser according to claim 5, wherein the connection between the central section of the geyser and each of the first and second end sections includes at least one elastomeric seal.
 7. A geyser according to claim 6, wherein the engaging formations on the central section and on the first and second end sections are arranged to limit compressive loads applied to the elastomeric seals.
 8. A geyser according to claim 1, wherein the central section includes a plurality of modular components which are connected to one another.
 9. A geyser according to claim 8, wherein the modular components include male and/or female engaging components which are engaged with corresponding female and/or male engaging components on adjacent modular components and with corresponding female and/or male engaging components on the first and second end sections.
 10. A geyser according to claim 9, wherein each connection between adjacent modular components and between a modular component and an end section of the geyser includes at least one elastomeric seal.
 11. A geyser according to claim 10, wherein the engaging formations on the modular components and on the first and second end sections are arranged to limit compressive loads applied to the elastomeric seals.
 12. A geyser according to claim 9, wherein the end sections each include a male engaging formation, and the central section includes an adaptor component which includes a female engaging formation at each of two opposed ends, and a plurality of modular components each of which includes a male engaging formation at one end and a female engaging formation at an opposed end, wherein the adaptor component is connected at each end to one of the modular components, the first and second end sections are each connected to one of the modular components, and each modular component is connected to at least one other modular component.
 13. A geyser according to claim 9, wherein the end sections each include a female engaging formation, and the central section includes an adaptor component which includes a male engaging formation at each of two opposed ends, and a plurality of modular components each of which includes a female engaging formation at one end and a male engaging formation at an opposed end, wherein the adaptor component is connected at each end to one of the modular components, the first and second end sections are each connected to one of the modular components, and each modular component is connected to at least one other modular component.
 14. A geyser according to claim 9, wherein the central section includes two different types of modular components, a first modular component with female engaging formations at each of two opposed ends thereof, and a second modular component with male engaging formations at each of two opposed ends thereof, wherein the first and second end sections are each connected to one of the first modular components, and each second modular component is connected at each end to one of the first modular components.
 15. A geyser according to claim 12, wherein each connection includes at least one elastomeric seal.
 16. A geyser according to claim 15, wherein the engaging formations at each connection are arranged to limit compressive loads applied to the elastomeric seals.
 17. A geyser according to claim 1 including external and/or internal bracing.
 18. A geyser according to claim 17, including reinforcing frames which extend across the inside of the central section.
 19. A geyser according to claim 18, wherein the reinforcing frames define a row of ribs along the length of the central section.
 20. A geyser according to claim 17, including a screen for limiting the flow of fluid entering the geyser.
 21. A geyser according to claim 20, wherein the screen is connected to at least a portion of the internal bracing.
 22. A geyser according to claim 17, including reinforcing ribs between the inner wall and the outer wall of the central section.
 23. A geyser according to claim 1, wherein the central section is connected to the first and second end sections with mechanical fasteners.
 24. A geyser according to claim 23, wherein the mechanical fasteners comprise a plurality of bolts which extend through the first end section and the central section, and which are connected to the second end section by means of a plurality of nuts.
 25. A geyser according to claim 1, wherein the secondary, safety chamber contains an insulation material.
 26. A geyser according to claim 25, wherein the insulation material comprises a polyurethane foam.
 27. A geyser according to claim 1, wherein the end sections each include an end face which is curved convexly with respect to the primary chamber.
 28. A geyser according to claim 27, including an insulated chamber on at least one of the end sections for insulating at least portions of electrical components for the geyser.
 29. A geyser according to claim 1, wherein the first and second end sections include supports for supporting the geyser, in use.
 30. A geyser according to claim 1, wherein the central section and the first and second end sections are formed from a polymer material.
 31. A method of making a geyser comprising the steps of: providing a first end section; providing a second end section; providing a central section which defines an inner wall and an outer wall spaced from the inner wall; connecting the central section to the first and second end sections so that the inner wall together with the first and second end sections forms a primary, sealed chamber for containing fluid within the geyser, in use, and the outer wall together with the inner wall and the first and second end sections forms a secondary, safety chamber for containing fluid expelled from the primary chamber upon failure of the geyser; and providing an outlet for allowing fluid to discharge from the secondary, safety chamber to a desired location.
 32. A method according to claim 31, wherein the steps of providing the central section and the first and second end sections include forming these sections in an injection molding process.
 33. A method according to claim 32, wherein the central section and the first and second end sections are formed from a polymer material.
 34. A method according to claim 31, wherein the step of connecting the central section to the first and second end sections includes locating elastomeric seals between the various sections.
 35. A method according to claim 31, wherein the central section includes a plurality of modular components, and the method includes the step of connecting the modular components together with elastomeric seals to form the central section.
 36. A method according to claim 35, wherein the central section and/or the first and second end sections are formed with external and/or internal bracing.
 37. A method according to claim 31, wherein the end sections and the central section are connected together by means of mechanical fasteners.
 38. A method according to claim 31, including the step of inserting an insulating material into the secondary chamber.
 39. A method according to claim 38, wherein the insulating material is a polyurethane foam.
 40. A kit for forming a geyser comprising: a first end section; a second end section; a central section defining an inner wall and an outer wall spaced from the inner wall, wherein the first section and the second section are connectable to the central section so that the inner wall together with the first and second end sections forms a primary, sealed chamber for containing fluid within the geyser, in use, and the outer wall together with the inner wall and the first and second end sections forms a secondary, safety chamber for containing fluid expelled from the primary chamber upon failure of the geyser; and an outlet in the first end section, the second end section and/or the central section for allowing fluid to discharge from the secondary, safety chamber to a desired location, in use.
 41. A kit according to claim 40, wherein the central section includes a plurality of modular components which are connectable to one another.
 42. A kit according to claim 40, including mechanical fasteners for connecting the first end section and the second end section to the central section. 